S/PDIF vs. USB interface for DAC

[DarkOne]

Hi All,

I've been reading stereophile's very positive review of Wavelenght audio USB DAC, where Art Dudley claimed that USB interface is superior to S/PDIF (Article) ,so I'd like to ask if its true. I'd like to use USB or S/PDIF receivcer with AD1865 DAC, but I don't know which interface is better for SQ.

Thanks

Regards
Robo

[fmak]

[QUOTE]Originally posted by DarkOne
[B]Hi All,

I've been reading stereophile's very positive review of Wavelenght audio USB DAC, where Art Dudley claimed that USB interface is superior to S/PDIF
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Don't know. What I do know is that there are all sorts of problems with usb drivers and computer stability including tendency to interference.

If you ask the computer guys, they will tell you that usb is perefct. But I have not found the kind of rigorous measurements in computer audio as in hifi. The Rightmark test software they use is to me questionable, having compared the results with my hirez FFT analyser.

Having said this, computer audio via usb or spdif does sound ok and fine to me. But it is difficult to compare this with a high end system.

It's time that Stereophile does a proper comparison.

[DarkOne]

I don't want to compare something with highend dac, I just want to make my own dac, which will be as good as I can make it. Maybe it will be better, maybe worse, time and final result will show. I just wanted to ask if somebody compared these two interfaces. I guess that S/PDIF is much easier to implement, but I want to make maximum for sq.

Here's part of that article, which made me think about interfaces:
According to Rankin, the S/PDIF environment is more prone to unwanted variations in the frequency of the incoming word-clock signal, which the converter is always trying to track. But with a USB controller generating its own word-clock signal, the frequency remains steady.

As I understand it properly, it's all about jitter, nothing more, nothing less.

[bocka]

According to Rankin, the S/PDIF environment is more prone to unwanted variations in the frequency of the incoming word-clock signal, which the converter is always trying to track. But with a USB controller generating its own word-clock signal, the frequency remains steady.

This is completely BS. USB is one of the most crappy interfaces, I've ever seen. It's a lowest cost, lowest quality, consumer interface connecting everything to the PC. Although SPDIF has it weaks details, it was designed for audio at least. With an USB interface you're getting uncontrolled ground loops as well as EMI coupling everywhere.

[ble0t]

I'm sure this has probably been posted before, but this is a very good article about the creation of (including resolution of problems) a USB DAC...

http://www.planetanalog.com/showArti...cleID=12801995

[Jocko Homo]

Stereophile says/writes something, and everyone believes it.

It is a sick world...................

Jocko

[cyteen]

Pedja compared a spAct based usb dac with a similarly constructed spdif dac here:

http://www.diyhifi.org/forums/viewtopic.php?p=6869#6869

which resulted in the differences between the two being lost in the variance between different batches of the dac used.

[DarkOne]

Originally posted by Jocko Homo
Stereophile says/writes something, and everyone believes it.

It is a sick world...................

Jocko

I don't believe it, it just made me think about it and then ask about it here.

[inatightspot]

From the replies already posted, I gather that you realize that stereophile's opinion of what is the current state of the art is at best questionable. I don't remember reading a negative comment about a reviewed product for quite some time. And if you have read any of Dudley's other reviews you may get the impresssion that he just likes to read what he writes.
s/pdif isn't great but we're stuck with it. And now it's finally better than analog, so what's the problem?

[DarkOne]

I know how magazines work. I've been working for local coputer magazine for 4 years and I know that it's all about money. Magazine will never publish a negative review.

Anyway, the statement that USB is superior to S/PDIF made me think about it. And because I'm currently starting to work on my own DAC, I just asked.